Power over Ethernet (PoE) devices are classified into Ethernet power sourcing equipments and Ethernet powered devices. An Ethernet power sourcing equipment supplies power to an Ethernet powered device through an Ethernet cable. Generally, an Ethernet power sourcing equipment can provide a single Ethernet powered device with a maximum power of 30 watts (W). In recent years, as a cloud technology develops, increasing types of devices, such as cloud terminals, high definition cameras, and notebook computers, can be supported by remote power supply applications. Power requirements of these devices may be greater than 30 W, and may even reach 60 W or 90 W. After such a high-power Ethernet powered device is connected to a power over Ethernet system, the Ethernet power sourcing equipment may be overloaded, or the use of multiple low-power Ethernet powered devices may be affected.